Sarcopenia in colorectal cancer is related to socio-economic deprivation and Body Mass Index alone misrepresents underlying muscle loss in the deprived.

BACKGROUND & AIMS: Patients with colorectal cancer who are more socio-economically deprived have worse outcomes; deprivation is also associated with higher obesity rates, defined as a body mass index (BMI) of greater than thirty. Body composition (BC) factors such as sarcopenia and myosteatosis are also known to predispose to poorer outcomes following colorectal cancer surgery. There is limited evidence to date to relate the effect of deprivation upon these host characteristics that are linked to prognosis. We aimed to examine the relationship between deprivation and body composition in colorectal cancer. METHODS: Analysis was performed on a prospectively collected database of preoperative primary colorectal cancer patients at St Mark's - The National Bowel Hospital, UK. Body composition characteristics were identified by analysing the L3 axial slices of Computer Tomogram (CT) slices of preoperative staging using Slice-O-Matic software with Automatic Body composition Analyser using Computed tomography image Segmentation (ABACS) L3 plug-in. Deprivation status for each patient was determined using their postal code which was linked to the Index of Multiple Deprivation (IMD). Each domain of the IMD was examined individually in relation to BC characteristics. Binary logistic regression analysis was performed on the data using a model developed from previous published analyses of this dataset. RESULTS: Four hundred and nineteen patients were included in the final analysis, the median age was 69 years and 57% of the patient population was male. Patients who were more deprived were significantly more likely to be sarcopenic [OR 1.56 (95% CI 1.01-2.41, p = 0.045)] and myosteatotic [OR 1.69 (95% CI 1.019-2.81, p = 0.042)]. More deprived patients were also more likely to have a lower BMI [OR 0.60 (95% CI 0.38-0.94, p = 0.026)] despite no significant difference in visceral obesity between the most and least deprived. CONCLUSIONS: Deprivation is an important independent determinant of sarcopenia in the colorectal cancer population. Identifying these patients early and addressing reversible factors may help improve post-operative surgical outcomes in this poor prognostic group. Sarcopenia may be a premorbid state in the deprived colorectal cancer patient that may not be wholly driven by tumour characteristics.

Perianal Fistulizing Crohn's Disease-Associated Anorectal and Fistula Cancers: Systematic Review and Expert Consensus.

BACKGROUND & AIMS: Perianal fistulizing Crohn's disease (PFCD)-associated anorectal and fistula cancers are rare but often devastating diagnoses. However, given the low incidence and consequent lack of data and clinical trials in the field, there is little to no guidance on screening and management of these cancers. To inform clinical practice, we developed consensus guidelines on PFCD-associated anorectal and fistula cancers by multidisciplinary experts from the international TOpClass consortium. METHODS: We conducted a systematic review by standard methodology, using the Newcastle-Ottawa Scale quality assessment tool. We subsequently developed consensus statements using a Delphi consensus approach. RESULTS: Of 561 articles identified, 110 were eligible, and 76 articles were included. The overall quality of evidence was low. The TOpClass consortium reached consensus on 6 structured statements addressing screening, risk assessment, and management of PFCD-associated anorectal and fistula cancers. Patients with long-standing (>10 years) PFCD should be considered at small but increased risk of developing perianal cancer, including squamous cell carcinoma of the anus and anorectal carcinoma. Risk factors for squamous cell carcinoma of the anus, notably human papilloma virus, should be considered. New, refractory, or progressive perianal symptoms should prompt evaluation for fistula cancer. There was no consensus on timing or frequency of screening in patients with asymptomatic perianal fistula. Multiple modalities may be required for diagnosis, including an examination under anesthesia with biopsy. Multidisciplinary team efforts were deemed central to the management of fistula cancers. CONCLUSIONS: Inflammatory bowel disease clinicians should be aware of the risk of PFCD-associated anorectal and fistula cancers in all patients with PFCD. The TOpClass consortium consensus statements outlined herein offer guidance in managing this challenging scenario.

Sarcopenia is independently associated with poor preoperative physical fitness in patients undergoing colorectal cancer surgery.

BACKGROUND: Accurate preoperative risk assessment for major colorectal cancer (CRC) surgery remains challenging. Body composition (BC) and cardiopulmonary exercise testing (CPET) can be used to evaluate risk. The relationship between BC and CPET in patients undergoing curative CRC surgery is unclear. METHODS: Consecutive patients undergoing CPET prior to CRC surgery between 2010 and 2020 were identified between two different UK hospitals. Body composition phenotypes such as sarcopenia, myosteatosis, and visceral obesity were defined using widely accepted thresholds using preoperative single axial slice CT image at L3 vertebrae. Relationships between clinicopathological, BC, and CPET variables were investigated using linear regression analysis. RESULTS: Two hundred eighteen patients with stage I-III CRC were included. The prevalence of sarcopenia, myosteatosis, and visceral obesity was 62%, 33%, and 64%, respectively. The median oxygen uptake at anaerobic threshold (VO2 at AT) was 12.2 mL/kg/min (IQR 10.6-14.2), and oxygen uptake at peak exercise (VO2 peak) was 18.8 mL/kg/min (IQR 15.4-23). On univariate linear regression analysis, male sex (P < 0.001) was positively associated with VO2 at AT. While ASA grade (P < 0.001) and BMI (P = 0.007) were negatively associated with VO2 at AT, on multivariate linear regression analysis, these variables remained significant (P < 0.05). On univariate linear regression analysis, male sex (P < 0.001) was positively associated with VO2 peak, whereas age (P < 0.001), ASA grade (P < 0.001), BMI (P = 0.003), sarcopenia (P = 0.015), and myosteatosis (P < 0.001) were negatively associated with VO2 peak. On multivariate linear regression analysis age (P < 0.001), ASA grade (P < 0.001), BMI (P < 0.001), and sarcopenia (P = 0.006) were independently and negatively associated with VO2 peak. CONCLUSIONS: The novel finding that sarcopenia is independently associated with reduced VO2 peak performance in CPET supports the supposition that reduced muscle mass relates to poor physical function in CRC patients. Further work should be undertaken to assess whether sarcopenia diagnosed on CT can act as suitable surrogate for CPET to further enhance personalized risk stratification.

Exploring methods of improving patient understanding and communication in a complex anal fistula clinic: results from a randomized controlled feasibility study.

AIM: Patient understanding of disease can guide decision-making in the management of anal fistula. This prospective feasibility study aimed to assess the acceptability and methods of assessing the impact of viewing realistic models on patients with anal fistula. METHODS: New referrals to a tertiary clinic participated in this single-centre, parallel-group randomized controlled study. Baseline characteristics, Decisional Conflict Scale and understanding of disease were assessed pre-consultation. Participants were randomized to a standard consultation, where disease and treatment options were explained using magnetic resonance images and drawn diagrams, or a similar consultation supplemented with an appropriate generic three-dimensional (3D) printed model. Understanding of disease and proposed surgery, Decisional Conflict Scale and ratings of visual aids were assessed post-consultation, along with 3D model feedback. RESULTS: All 52 patients who were approached agreed to be randomized (25 standard, 27 3D consultation). Understanding of disease increased post-consultation in both groups. Post-consultation decisional conflict (0, no; 100, high decisional conflict) was low (median 27 post-standard vs. 24 post-3D consultation). Patients scored highly on measures assessing understanding of proposed surgery. 3D models were rated highly, with 96% of patients wanting to see them again in future consultations. CONCLUSIONS: Three-dimensional printed fistula models are a welcome addition to outpatient consultations with results suggesting that understanding of surgery is improved. A future trial should be powered to detect whether 3D models result in a significant improvement in understanding beyond traditional methods of explanation and explore the conditions in which models have their maximal utility. GOV REGISTRATION ID: This study was registered on ClinicalTrials.gov (ID: NCT04069728). Registered on 23 August 2019.

A systematic review of automated segmentation of 3D computed-tomography scans for volumetric body composition analysis.

Automated computed tomography (CT) scan segmentation (labelling of pixels according to tissue type) is now possible. This technique is being adapted to achieve three-dimensional (3D) segmentation of CT scans, opposed to single L3-slice alone. This systematic review evaluates feasibility and accuracy of automated segmentation of 3D CT scans for volumetric body composition (BC) analysis, as well as current limitations and pitfalls clinicians and researchers should be aware of. OVID Medline, Embase and grey literature databases up to October 2021 were searched. Original studies investigating automated skeletal muscle, visceral and subcutaneous AT segmentation from CT were included. Seven of the 92 studies met inclusion criteria. Variation existed in expertise and numbers of humans performing ground-truth segmentations used to train algorithms. There was heterogeneity in patient characteristics, pathology and CT phases that segmentation algorithms were developed upon. Reporting of anatomical CT coverage varied, with confusing terminology. Six studies covered volumetric regional slabs rather than the whole body. One study stated the use of whole-body CT, but it was not clear whether this truly meant head-to-fingertip-to-toe. Two studies used conventional computer algorithms. The latter five used deep learning (DL), an artificial intelligence technique where algorithms are similarly organized to brain neuronal pathways. Six of seven reported excellent segmentation performance (Dice similarity coefficients > 0.9 per tissue). Internal testing on unseen scans was performed for only four of seven algorithms, whilst only three were tested externally. Trained DL algorithms achieved full CT segmentation in 12 to 75 s versus 25 min for non-DL techniques. DL enables opportunistic, rapid and automated volumetric BC analysis of CT performed for clinical indications. However, most CT scans do not cover head-to-fingertip-to-toe; further research must validate using common CT regions to estimate true whole-body BC, with direct comparison to single lumbar slice. Due to successes of DL, we expect progressive numbers of algorithms to materialize in addition to the seven discussed in this paper. Researchers and clinicians in the field of BC must therefore be aware of pitfalls. High Dice similarity coefficients do not inform the degree to which BC tissues may be under- or overestimated and nor does it inform on algorithm precision. Consensus is needed to define accuracy and precision standards for ground-truth labelling. Creation of a large international, multicentre common CT dataset with BC ground-truth labels from multiple experts could be a robust solution.

The development of a minimum dataset for MRI reporting of anorectal fistula: a multi-disciplinary, expert consensus process.

There are a range of sphincter-preserving procedures available to treat anorectal fistula, some of which can be precluded, or rendered more optimal by specific features of fistula anatomy. Magnetic resonance imaging (MRI) is the gold standard modality for assessing anorectal fistula. To maximise clinical utility, the MRI report should accurately describe these clinically relevant features. We aimed to develop a minimum dataset for reporting MRI of anorectal fistula, in order to improve the assessment and management of these patients. A longlist of 70 potential items for the minimum dataset was generated through systematic review of the literature. This longlist was presented to radiologists, surgeons and gastroenterologists in an online survey to understand the features that shape current clinical practice. The longlist and survey results were then presented to an expert consensus panel to generate the final minimum dataset through discussion and anonymous voting. The final minimum dataset details the general characteristics, features of the internal and external openings, path of the fistula through the sphincters and any associated extensions and collections that should be described in all MRI reports for anal fistula. Additional surgical and perianal Crohn's disease subsets were developed to indicate the features that aid decision-making for these patients, in addition to a minimum dataset for the clinical request. This study represents a multi-disciplinary approach to developing a minimum dataset for MRI reporting of anal fistula, highlighting the most important features to report that can assist in clinical decision-making. KEY POINTS: • This paper recommends the minimum features that should be included in all MRI reports for the assessment of anal fistula, including Parks classification, number of tracts, features of the internal and external opening, path of the tract through the sphincters, the presence and features of extensions and collections. • Additional features that aid decision-making for surgery or in the presence of Crohn's disease have been identified. • The items that should be included when requesting an MRI are specified.

Systematic Review: The Impact and Importance of Body Composition in Inflammatory Bowel Disease.

BACKGROUND AND AIMS: Alterations in body composition are common in inflammatory bowel disease [IBD] and have been associated with differences in patient outcomes. We sought to consolidate knowledge on the impact and importance of body composition in IBD. METHODS: We performed a systematic search of MEDLINE, EMBASE and conference proceedings by combining two key research themes: inflammatory bowel disease and body composition. RESULTS: Fifty-five studies were included in this review. Thirty-one focused on the impact of IBD on body composition with a total of 2279 patients with a mean age 38.4 years. Of these, 1071 [47%] were male. In total, 1470 [64.5%] patients had Crohn's disease and 809 [35.5%] had ulcerative colitis. Notably, fat mass and fat-free mass were reduced, and higher rates of sarcopaenia were observed in those with active IBD compared with those in clinical remission and healthy controls. Twenty-four additional studies focused on the impact of derangements in body composition on IBD outcomes. Alterations in body composition in IBD are associated with poorer prognoses including higher rates of surgical intervention, post-operative complications and reduced muscle strength. In addition, higher rates of early treatment failure and primary non-response are seen in patients with myopaenia. CONCLUSIONS: Patients with IBD have alterations in body composition parameters in active disease and clinical remission. The impacts of body composition on disease outcome and therapy are broad and require further investigation. The augmentation of body composition parameters in the clinical setting has the potential to improve IBD outcomes in the future.

Classifying perianal fistulising Crohn's disease: an expert consensus to guide decision-making in daily practice and clinical trials.

Perianal fistulising Crohn's disease is an aggressive disease phenotype that can have a substantial detrimental impact on patients' quality of life. Current biological understanding of perianal fistulising Crohn's disease remains inadequate and previous classification systems have not provided clear guidance on therapy in clinical practice nor on defining patient cohorts within clinical trials. We propose a new classification system for perianal fistulising Crohn's disease that was developed through a modified nominal group technique expert consensus process. The classification identifies four groups of patients. Key elements include stratification according to disease severity as well as disease outcome; synchronisation of patient and clinician goals in decision making, with a proactive, combined medical and surgical approach, on a treat to patient goal basis; and identification of indications for curative fistula treatment, diverting ostomy, and proctectomy. The new classification retains an element of flexibility, in which patients can cycle through different classes over time. Furthermore, with each specific class comes a paired treatment strategy suggestion and description of clinical trial suitability. The proposed classification system is the first of its kind and is an important step towards tailored standardisation of clinical practice and research in patients with perianal fistulising Crohn's disease.

Colorectal Cancer: Performance and Evaluation for CT Colonography Screening- A Multicenter Cluster-randomized Controlled Trial.

Background Most radiologists reporting CT colonography (CTC) do not undergo compulsory performance accreditation, potentially lowering diagnostic sensitivity. Purpose To determine whether 1-day individualized training in CTC reporting improves diagnostic sensitivity of experienced radiologists for 6-mm or larger lesions, the durability of any improvement, and any associated factors. Materials and Methods This prospective, multicenter cluster-randomized controlled trial was performed in National Health Service hospitals in England and Wales between April 2017 and January 2020. CTC services were cluster randomized into intervention (1-day training plus feedback) or control (no training or feedback) arms. Radiologists in the intervention arm attended a 1-day workshop focusing on CTC reporting pitfalls with individualized feedback. Radiologists in the control group received no training. Sensitivity for 6-mm or larger lesions was tested at baseline and 1, 6, and 12 months thereafter via interpretation of 10 CTC scans at each time point. The primary outcome was the mean difference in per-lesion sensitivity between arms at 1 month, analyzed using multilevel regression after adjustment for baseline sensitivity. Secondary outcomes included per-lesion sensitivity at 6- and 12-month follow-up, sensitivity for flat neoplasia, and effect of prior CTC experience. Results A total of 69 hospitals were randomly assigned to the intervention (31 clusters, 80 radiologists) or control (38 clusters, 59 radiologists) arm. Radiologists were experienced (median, 500-999 CTC scans interpreted) and reported CTC scans routinely (median, 151-200 scans per year). One-month sensitivity improved after intervention (66.4% [659 of 992]) compared with sensitivity in the control group (42.4% [278 of 655]; difference = 20.8%; 95% CI: 14.6, 27.0; P < .001). Improvements were maintained at 6 (66.4% [572 of 861] vs 50.5% [283 of 560]; difference = 13.0%; 95% CI: 7.4, 18.5; P < .001) and 12 (63.7% [310 of 487] vs 44.4% [187 of 421]; difference = 16.7%; 95% CI: 10.3, 23.1; P < .001) months. This beneficial effect applied to flat lesions (difference = 22.7%; 95% CI: 15.5, 29.9; P < .001) and was independent of career experience (≥1500 CTC scans: odds ratio = 1.09; 95% CI: 0.88, 1.36; P = .22). Conclusion For radiologists evaluating CT colonography studies, a 1-day training intervention yielded sustained improvement in detection of clinically relevant colorectal neoplasia, independent of previous career experience. Clinical trial registration no. NCT02892721 © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Pickhardt in this issue. An earlier incorrect version appeared online and in print. This article was corrected on February 28, 2022.

The impact of three-dimensional reconstruction and standardised CT interpretation (AMIGO) on the anatomical understanding of mesenteric vascular anatomy for planning complete mesocolic excision surgery: A randomised crossover study.

BACKGROUND: Preoperative planning is a crucial aspect of safe complete mesocolic excision (CME) surgery. 3D models derived from imaging may help improve anatomical understanding of the complex vascular anatomy. Here, we assessed the effect of 3D models on surgeons' anatomical understanding in comparison to a systematic approach for CT scan interpretation (AMIGO). METHOD: Fifteen cases were included in the study. Two GI radiology consultants reviewed each scan to ascertain the vascular anatomy. Virtual 3D models were produced and displayed on a web-based platform (https://skfb.ly/6OZUZ). A total of 13 surgical trainees were recruited. Candidates were assessed after baseline anatomical training and subsequently using the AMIGO method and 3D models. Five cases were randomly allocated in each round of testing for each participant. The primary outcome measure was an objective vascular anatomy knowledge score. The secondary outcome measure was subjective feedback from participants. RESULTS: Both 3D and AMIGO significantly improved anatomical understanding in comparison to baseline testing. However, 3D was superior to AMIGO (3D [n = 65; median score 8/14] vs. AMIGO [n = 65; median score 6/14; p < 0.0001]. For 13/15 patient cases examined, 3D was superior to the AMIGO method. Eleven participants demonstrated better anatomical understanding using 3D models versus AMIGO. Ten participants preferred 3D models in comparison to standard CT imaging. CONCLUSIONS: 3D models improve anatomical understanding of mesenteric vascular anatomy in a group of colorectal surgical trainees in comparison to a formal CT interpretation method. 3D models may be a useful planning adjunct to 2D imaging for CME surgery.

Current review of the management of fistulising perianal Crohn's disease.

Perianal manifestations of Crohn's disease constitute a distinct disease phenotype commonly affecting patients and conferring an increased risk of disability and disease burden. Much research has gone into management of fistulising manifestations, with biological therapy changing the landscape of treatment. In this article, we discuss the up-to-date surgical and medical management of perianal fistulas, highlighting current consensus management guidelines and the evidence behind them, as well as future directions in management.

Vascularity of Intra-testicular Lesions: Inter-observer Variation in the Assessment of Non-neoplastic Versus Neoplastic Abnormalities After Vascular Enhancement With Contrast-Enhanced Ultrasound.

The aim of this study is to assess the additional benefit of contrast-enhanced ultrasound (CEUS) over conventional ultrasonography (US) in identifying intra-testicular abnormalities among observers of different experiences. In this study, 91 focal testicular lesions (46 neoplastic, 45 non-neoplastic) imaged with gray-scale US/Doppler US and CEUS were classified using a 5-point scale. Three experienced and four inexperienced observers rated each lesion using gray-scale/color Doppler US alone and then with the addition of CEUS. Improved diagnostic specificity and accuracy with the addition of CEUS was observed for both experienced (specificity: 71.1% vs. 59.3%, p = 0.005; accuracy: 83.5% vs. 76.9%, p = 0.003) and inexperienced observers (specificity: 75.6% vs. 51.7%, p = 0.005; accuracy: 80.2% vs. 72.0%, p < 0.001). Significant inter-observer variability between the experienced and inexperienced observers when assessing conventional US alone was eliminated with the addition of CEUS. CEUS improves diagnostic accuracy of focal intra-testicular lesions for both experienced and inexperienced observers and reduces inter-observer variability in inexperienced operators.

Survival and CT defined sarcopenia in patients with intestinal failure on home parenteral support.

BACKGROUND & AIMS: Sarcopenia occurs in patients with intestinal failure (IF) and has been associated with poorer survival in several chronic diseases. CT can measure sarcopenia through a L3 skeletal muscle index (LSMI). We aim to describe the prevalence of sarcopenia in a section of our IF population using LSMI, & evaluate the effect of home parenteral support (PS) on LSMI & survival. Additionally, we aim to assess any association between LSMI, BMI & other anthropometric measurements. METHODS: IF patients on PS treated at St Mark's Hospital between 1/1/2006-1/10/2016 were identified from a prospectively maintained database. Patients were included if they were on PS & had 2 CTs: the first ≤30 days before start of HPN (pre-PS); the second ≥100 days from PS start (post-PS). Patient records were reviewed to obtain clinical & demographic information & date of death. Anthropometric measurements & BMI contemporaneous to CT scans were recorded. RESULTS: 64 patients met inclusion criteria (M:F 1:1). 83% of our cohort had LSMI below previously published thresholds for sarcopenia. Mean (SD) pre-PS LSMI was 36.5 (6.8)cm2/m2. Mean BMI pre-PS was 22.1 (4.8) kg/m2. Both BMI (22.1 kg/m2 to 23.5 kg/m2) p < 0.001) & LSMI (36.5 cm2/m2 to 38.4 cm2/m2) (p = 0.003) increased post-PS. A positive correlation was seen between BMI & LSMI pre (r = 0.47 p < 0.001) & post-PS (r = 0.37 p = 0.003). No correlation was seen between LSMI & anthropometric measurements pre-PS (p = 0.78) or post-PS (p = 0.96). 11 (17%) patients died during the study period; a low LSMI pre-PS was not a risk factor for mortality (HR 0.97 p = 0.55). CONCLUSIONS: This study is the first to look at sarcopenia & survival using CT defined LSMI (CT-LSMI) in the IF population. 83% of our cohort had a pre-PS LSMI below previously published thresholds, yet we found no relationship between lower baseline LSMI & survival. This may reflect the heterogeneity of the prognoses of the IF population, or that parenteral nutrition itself affects survival. Our study showed that LSMI & BMI improved following PS but demonstrated that other anthropometric measurements had poor correlation with LSMI & showed no significant improvement overall after PS, confirming the known problems of inter-operator & patient variability of these measurements. Whilst we found significant correlation between LSMI & BMI, BMI significantly underestimated the presence & degree of sarcopenia. LSMI has the potential to provide an objective & reproducible measure of sarcopenia in IF. Future larger studies should be performed to evaluate associations with patient outcomes & utility in clinical decision making.

Developing a core outcome set for fistulising perianal Crohn's disease.

OBJECTIVE: Lack of standardised outcomes hampers effective analysis and comparison of data when comparing treatments in fistulising perianal Crohn's disease (pCD). Development of a standardised set of outcomes would resolve these issues. This study provides the definitive core outcome set (COS) for fistulising pCD. DESIGN: Candidate outcomes were generated through a systematic review and patient interviews. Consensus was established via a three-round Delphi process using a 9-point Likert scale based on how important they felt it was in determining treatment success culminating in a final consensus meeting. Stakeholders were recruited nationally and grouped into three panels (surgeons and radiologists, gastroenterologists and IBD specialist nurses, and patients). Participants received feedback from their panel (in the second round) and all participants (in the third round) to allow refinement of their scores. RESULTS: A total of 295 outcomes were identified from systematic reviews and interviews that were categorised into 92 domains. 187 stakeholders (response rate 78.5%) prioritised 49 outcomes through a three-round Delphi study. The final consensus meeting of 41 experts and patients generated agreement on an eight domain COS. The COS comprised three patient-reported outcome domains (quality of life, incontinence and a combined score of patient priorities) and five clinician-reported outcome domains (perianal disease activity, development of new perianal abscess/sepsis, new/recurrent fistula, unplanned surgery and faecal diversion). CONCLUSION: A fistulising pCD COS has been produced by all key stakeholders. Application of the COS will reduce heterogeneity in outcome reporting, thereby facilitating more meaningful comparisons between treatments, data synthesis and ultimately benefit patient care.

Persistent Fistula After Anorectal Abscess Drainage: Local Experience of 11 Years.

BACKGROUND: The characteristics of patients who develop a fistula-in-ano after an anorectal abscess are unclear. OBJECTIVE: Our study explored this relationship and patient factors associated with fistula development. DESIGN: International Classification of Diseases, 10 Revision, and Classification of Interventions and Procedures, version 4, codes were used to identify all of the patients with a primary anorectal abscess. Multivariable analysis was used to identify factors predictive of fistula formation. SETTINGS: The study was conducted in a district general hospital. PATIENTS: Patients with anorectal abscess who were admitted to our institution (2004-2015) were included. MAIN OUTCOMES MEASURES: The rate of subsequent fistula formation was measured. RESULTS: A total of 1970 abscess patients were identified; 70.0% (n = 1379) were men, and 7.3% (n = 144) had Crohn's disease. Fistulas occurred in 16.2% (n = 319) at a median of 7 months (interquartile range, 3-7 mo). Patients with Crohn's disease were more than twice as likely to develop a fistula than patients without Crohn's disease (32.6% vs 14.9%; OR = 2.5 (95% CI, 1.7-3.7); p < 0.001). Patients with Crohn's disease with a fistula were more likely to be women (55.3% vs 34.6%; p = 0.007) and aged <30 years (51.1% vs 24.3%; p< 0.001) versus patients without Crohn's disease with a fistula. At multivariable analysis of the entire cohort, male sex (OR = 0.7 (95% CI, 0.5-0.9); p = 0.005) and diabetes mellitus (OR = 0.5 (95% CI, 0.3-0.9); p = 0.027) were associated with a reduced likelihood of developing a fistula after abscess formation. LIMITATIONS: The study was limited by its single-center scope, retrospective analysis, and lack of a standardized definition for Crohn's disease. CONCLUSIONS: Abscesses are more common in men, but progression to fistula is more likely in women. The rate of fistula progression in Crohn's disease is twice that in patients without Crohn's disease. Identification of patients at risk may help delineate those who will benefit from a more conservative surgical approach, enhanced follow-up, or investigation after abscess drainage. See Video Abstract at http://links.lww.com/DCR/A798.

Innovation in the imaging perianal fistula: a step towards personalised medicine.

BACKGROUND: Perianal fistula is a topic both hard to understand and to teach. The key to understanding the treatment options and the likely success is deciphering the exact morphology of the tract(s) and the amount of sphincter involved. Our aim was to explore alternative platforms better to understand complex perianal fistulas through three-dimensional (3D) imaging and reconstruction. METHODS: Digital imaging and communications in medicine images of spectral attenuated inversion recovery magnetic resonance imaging (MRI) sequences were imported onto validated open-source segmentation software. A specialist consultant gastrointestinal radiologist performed segmentation of the fistula, internal and external sphincter. Segmented files were exported as stereolithography files. Cura (Ultimaker Cura 3.0.4) was used to prepare the files for printing on an Ultimaker 3 Extended 3D printer. Animations were created in collaboration with Touch Surgery™. RESULTS: Three examples of 3D printed models demonstrating complex perianal fistula were created. The anatomical components are displayed in different colours: red: fistula tract; green: external anal sphincter and levator plate; blue: internal anal sphincter and rectum. One of the models was created to be split in half, to display the internal opening and allow complexity in the intersphincteric space to better evaluated. An animation of MRI fistulography of a trans-sphincteric fistula tract with a cephalad extension in the intersphincteric space was also created. CONCLUSION: MRI is the reference standard for assessment of perianal fistula, defining anatomy and guiding surgery. However, communication of findings between radiologist and surgeon remains challenging. Feasibility of 3D reconstructions of complex perianal fistula is realized, with the potential to improve surgical planning, communication with patients, and augment training.

Symptom Amelioration in Crohn's Perianal Fistulas Using Video-Assisted Anal Fistula Treatment (VAAFT).

BACKGROUND AND AIMS: A third of patients with Crohn's disease develop perianal fistulas. These are associated with a significant burden of symptoms and negative impact on quality of life. This study reports the use of video-assisted anal fistula treatment [VAAFT] as a means of symptom improvement; this is a minimally invasive technique to access fistula track, and diagnose/facilitate drainage of deep/complex secondary extensions with cauterization of excess inflammatory tissue. METHODS: Consecutive patients with complex Crohn's fistula undergoing VAAFT for symptomatic Crohn's anal fistula were included. They were identified from a prospectively maintained database, which was interrogated from June 2015 to November 2017. Patients underwent diagnostic fistuloscopy and fulguration of tracts/secondary extensions. Setons were sited/replaced after the procedure to maintain postoperative drainage. The primary endpoint was completion of the 'Measure your medical outcome profile' [MYMOP2] quality of life [QoL] questionnaire at 6 weeks postoperatively. Secondary outcome measures were a decisional regret scale [DRS], postoperative complications and the 30-day re-operation rate. RESULTS: Twenty-five patients underwent the procedure during the study period. In total, 21/25 patients [84%] provided MYMOP2 QoL data demonstrating a statistically significant improvement in both pain and discharge scores. Eighty-one per cent of patients who completed the questionnaire agreed/strongly agreed that the procedure was the right decision and no patient regretted undergoing the procedure. There was one re-operation but otherwise no complications. CONCLUSIONS: This study demonstrates the feasibility, safety and importantly an improvement in patient-reported outcomes in a series of patients undergoing VAAFT for complex Crohn's anal fistula. VAAFT reduces the main symptoms [pain and discharge] in patients with complex refractory anal fistulas.